• Title/Summary/Keyword: chemical structure

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Studies on Chemical Structure Determination of Polygonatum sibiricum Extracts(II) (황정(黃精) 추출물의 화학구조 결정에 관한 연구(II))

  • 신동수;김흥재;조수동;권기락;안철진;주우홍;강진호;문병호
    • Journal of Life Science
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    • v.9 no.2
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    • pp.212-215
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    • 1999
  • Biologically active compounds in Polygonatum sibiricum were extracted using organic solvents as hexane, CHC1$_3$, n-butanol corresponding each component. Compound II was purified from hexane layer and the chemical structure of compound II was characterized using IH-nmr, 13C-nmr, DEPT135, COSY, HMQC, HMBC spectrum and MS-spectrum. Consequently, the chemical structure of compound II was determined as 2-Hydroxy-3-(9,12-(9E,12E)-Octadecadienoyloxy) propanoic acid.

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Fabrication of 2-Dimensional ZnO Nanowall Structure (2차원 ZnO 나노벽 구조 제조)

  • Kim, Young-Jung;Cao, Guozhong;Kim, Yeong-Cheol;Ahn, Seung-Joon;Min, Joon-Won
    • Journal of the Korean Ceramic Society
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    • v.42 no.7 s.278
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    • pp.521-524
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    • 2005
  • ZnO 2-D nanowall structure with around 100 nm thickness, which is composed of tens of nm scale ZnO single crystals, was fabricated through the low temperature chemical solution growth method. Electro Chemical Deposition (ECD) technique was applied to attach the ZnO seed crystals on ITO coated glass substrate. The ZnO nanowall structure was grown in the 0.015 mol$\%$ of aqueous solution of zinc nitrate and hexamethenamine at 60$^{\circ}C$ for 20 - 40 h. The nanowall structure depends on the ECD condition or the applied voltage and duration time. The nanowall shows a photoluminescence around 550 - 700 nm spectrum range.

Synthesis of Metal-Organic Framework material Cu-BTC and its application for $CO_2$ adsorption (유기 금속 Framework Cu-BTC의 합성 및 이산화탄소 분리 응용)

  • Peng, Mei-Mei;Hemalatha, Pushparaj;Ganesh, Mani;Venkatachalam, Kandan;Oh, Han-Seok;Jang, Hyun-Tae
    • Proceedings of the KAIS Fall Conference
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    • 2011.05a
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    • pp.147-150
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    • 2011
  • A copper-based metal organic framework (MOF) named Cu-BTC, also known as HKUST-1, was successfully synthesized by using a solvothermal method. The properties of the Cu-BTC sample were characterized with Powder X-ray diffraction (XRD) for phase structure, Thermogravimetric analysis (TGA) for thermal stability, Scanning electron microscopy (SEM) for crystal structure, and Nitrogen adsorption-desorption for pore textural structure. The analysis results displayed that the Cu-BTC sample exhibited a good crystal structure with uniform size of octahedral particles. The BET data revealed a high surface area of $1457 \;m^2g^{-1}$ and a pore volume of $0.60\; cm^3g^{-1}$. The Cu-BTCs ample was also studied for $CO_2$ adsorption and exhibited a maximum $CO_2$ adsorption capacity of 170 mg/g of the sorbent (3.8 mol/kg) at $25^{\circ}C$.

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Chemistry of Tea Polyphenol in the Processing Method (차의 가공방법에 따른 Polyphenol 화학)

  • 안봉전
    • Food Science and Preservation
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    • v.5 no.1
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    • pp.97-104
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    • 1998
  • The chemical structure of low molecule polyphenol of tea was found as explained. Structure decision of pioanthocyanidin was possible to measure 1,700 molecule, hexamer by chemical basic of polyphenol. At present, structure of high molecule than of that can't be suspected and it is concemed that strong astrigent ccnpound of tea is polymer proanthocyanidin. Mush researches was required in structure decision and isolation of high molecule polyphenol complex. Structure decision will develope at the natural products in the furture.

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Structure and Physical Properties of $YSe_{1.83}$

  • 김성진;오훈정
    • Bulletin of the Korean Chemical Society
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    • v.16 no.6
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    • pp.515-518
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    • 1995
  • YSe1.83 was synthesized by vapor transport technique and its crystal structure was determined. The structure was isostructure of LaTe2-x, which was layered structure consisting of two-atom thick layers of YSe with distorted NaCl-type structure and one-atom thick layer of Se. The substructure of YSe1.83 was tetragonal with space group of P4/nmm and a=4.011(2) and c=8.261(3) Å with final R/Rw=6.4/6.9 %. The superstructure with asuper=2a, bsuper=6b and csuper=2c was found. The measurements of electronic and magnetic properties of this compound indicate that it is an electronic insulator and diamagnet.